Inside the Mobilator, Disney Live Entertainment's First Fully Autonomous Onstage Character

Walt Disney Imagineering has released a behind-the-scenes look at the Mobilator, the fully autonomous platform that drives WALL-E's wagon in Remember: A Disney & Pixar Stage Show aboard the Disney Adventure. The video breaks down how lidar, wheel odometry, and a downward-facing camera keep the untethered machine on course, and what it takes to power it.

Disney Live Entertainment's first fully autonomous computer-driven character is a wagon-hauling robot called the Mobilator, and Walt Disney Imagineering just explained how it works. In a new behind-the-scenes video, the team breaks down the machine that carries WALL-E through Remember: A Disney & Pixar Stage Show aboard the Disney Adventure, from the three systems that track its position to the battery bank that keeps it moving.

A character with no track

"After a few years of working together with our partners, we've managed to bring the Mobilator to life, our first fully autonomous computer-driven character on stage," a team member explains in the video. The platform is the driving force behind the WALL-E wagon and, as another puts it, "how we bring our second show, Remember, to life on the Disney Adventure."

"Technically, it's a really interesting and complex bit of machinery that we have not used before," the team says. The freedom is also the challenge: "When we have something that is completely autonomous and is not connected to a track, that adds another level of risk that we have to mitigate."

That risk calculation covers everything sharing the deck with it. "When we think about scenic and how we interact with performers and other pieces of scenic on our stage, we have to understand how these types of things are going to integrate."

Three systems tell it where it is

The Mobilator fuses three position readings at once. The first is lidar: the unit constantly emits "a small signal that is hitting reflectors that we have throughout the stage" and triangulates its position off those hits. "It knows within essentially the geo-fence of the stage that we've created where it is at all times," a team member says.

The second is wheel odometry from the casters, which the video describes as "basically just reading how many times is the wheel rotating and counting that" to track movement across the stage.

The third is a downward-facing camera that looks for coded markers, similar to QR codes, embedded in the stage floor. Those handle fine positioning in spots where close is not good enough, such as lining the wagon up on a lift before the lift is allowed to move. The team originally expected the cameras to lead navigation; in practice they became the backup, "a way to safely ensure that we are in the proper position" that adds "that extra element of safety and security about how we're moving about the stage."

Eight car batteries and a built-in ramp

Making the platform self-driving also means making it self-powered. Beneath the deck sits a battery bank the video compares to standard car batteries: "You've basically got eight of them wired up in series." Whenever there is a break, the unit heads home. "Every time we get an opportunity, we take this down to its home where we can connect it to its charging station to ensure that it's got the power to move about safely and efficiently," a team member says.

The deck also carries a ramp so performers and additional characters can climb on and move around freely while the wagon is in motion.

The show it drives

Remember: A Disney & Pixar Stage Show premiered with the Disney Adventure, Disney Cruise Line's Singapore-based ship, and stars WALL-E and EVE. When a power outage cuts their reunion short and leaves EVE deactivated, WALL-E sets out to reboot her, calling on characters from Disney and Pixar films such as Coco, The Little Mermaid, and Aladdin to help restore her memories. The Mobilator is what moves WALL-E's wagon through it all.

More from the series

The video is part of Great Moments in Imagineering & Disney Live Entertainment, a behind-the-scenes series on Walt Disney Imagineering's YouTube channel about the work behind Disney parks, resorts, attractions, and cruise ships. Earlier episodes include:

• The American Adventure behind the scenes
• We motion captured Scooter
• The future of animatronics

Why this matters

Trackless, self-navigating show pieces give designers staging options a fixed track cannot, and the Mobilator is the first time Disney Live Entertainment has trusted one with a lead character in a running show. Cruise fans can see it in person: Remember plays aboard the Disney Adventure, with itineraries at disneycruise.disney.go.com.